This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.
A wireless sensor network (WSN) is a network of spatially distributed, typically autonomous sensors (commonly called “nodes”, although a node might be connected to multiple sensors) to monitor physical or environmental conditions, such as temperature, sound, pressure, and the like. The nodes pass their data through the network generally to a main location, i.e., to a sink node. Such networks are used in many industrial and consumer applications, such as industrial process monitoring and control, machine health monitoring, health care monitoring, and area monitoring.
WSNs may occur in cellular systems, which means that the nodes are under control (at least in part) of base stations in the cellular systems. Thus, information to be transmitted or received between nodes may have to go through or be controlled by a base station. Such systems could be improved in certain situations, as described in more detail below.